Economics of Transportation最新文献

With a view to construct a new framework to assess the benefits of freight transport improvements, an Economic Order Quantity model with uncertain lead time demand is equipped with detailed transport costs. The problem is to minimise total logistics cost by choosing shipment size, vehicle size and reorder point subject to constraints on vehicle size and annual transport capacity. An analytical solution in all variables except the reorder point is derived, reducing the cost minimisation problem to a well-behaved problem in one dimension only.

Different parts of transport costs influence the solution differently: Some act like ordering costs, some like holding costs and some have no influence on the solution. The solution exhibits economies of scale at all levels of optimal shipment size.

Examples with real data show that model calibration for an entire population of firms is feasible at the firm level, and that the model produces reasonable results.

We study empirically the price dynamics in the long-distance bus market using posted fares by Flixbus, the market leader in Europe. We find that, at a given point in time, the fare increases with the number of sold seats. This result largely explains, why the lowest available fare increases as the departure date approaches. No evidence is found in favor of intertemporal price discrimination, probably because of low consumer-heterogeneity throughout the entire booking period that characterizes the long-distance bus market.

This paper uses the bottleneck model of Vickrey (1969) to empirically measure the social cost of traffic congestion in the US. Using a detailed trip-level data, we estimate extra travel time over and above hypothetical free-flow travel time, which we call “queuing time”, for each average commute trip. The estimated individual queuing time implies that the annual cost of congestion borne by all US commuters is about 29 billion dollars. We find that a higher level of congestion in a city may be attributed to a smaller per capita road stock in the city. This paper also empirically quantifies a toll that depends both on the commuter's arrival time and trip distance.

This paper is concerned with the Wider Economic Impacts (WEIs) of transport improvements that arise via scale economies of agglomeration. It reviews the background theory and empirical evidence on agglomeration, explains the link between transport and agglomeration, and describes a three step procedure to appraise agglomeration impacts in a number of different settings. It includes new analytical work on measures of agglomeration and reports agglomeration-productivity elasticity estimates for the UK not previously published in the academic literature. The paper concludes with a set of recommendations for future empirical work on agglomeration and transport appraisal.

This paper considers the following scheme for the joint provision of transportation infrastructure: two regions jointly establish an operator for the infrastructure who is then responsible for collecting the user charges. The two regions make financial contributions to cover the costs of the infrastructure investment, and the revenue from user charges is distributed according to the share of contribution. The governments of the two regions choose the contribution that maximizes their regional welfare. Assuming that the infrastructure use is non-rival, we show that financing the infrastructure with revenue from user charges is better than financing it with tax revenue. We extend the analysis by incorporating congestion in infrastructure use. We show that independent decisions on contributions by two governments attain the first-best optimum when the operator sets the user charge such that the toll revenue just covers the cost of the investment. We further examine the conditions under which two governments participate in joint provision at Nash equilibrium.

We study two districts’ voluntary co-financing of a centrally provided public good, e.g., transport infrastructure. Outcomes are compared to a surplus-maximizing level of public good provision. We show that both co-financing and lobbying raise the amount of public good provided. Co-financing and lobbying are substitutes. Co-financing (or co-financing combined with lobbying) raises the provision of the public good to a higher level than lobbying alone. Co-financing can thus reduce rent-seeking. Finally, we show that under uncertainty about district type (high or low benefit), co-financing combined with lobbying can be used to find and retain a separating equilibrium.

Weather shocks frequently impair the smooth functioning of transportation systems. We use a dataset consisting of 2.14 million flight departures from ten large U.S. airports between January 2012 and September 2017, and estimate the effects sudden onset events, i.e., precipitation and wind, and slow onset events, i.e., temperature, have on departure delay. For sudden onset events, we apply a difference-in-difference framework that allows for inferences at the hourly level. The effects of slow onset events on departure delay are estimated based on a Prais Winstein estimator with panel-corrected standard errors. Our estimates show a significant increase in departure delay of up to 23 min depending on the weather type and intensity of the disturbance. Given the social costs of schedule delays, these results are of high economic importance.

This paper addresses the problem of measuring the welfare benefits of a transport improvement. We formulate and analyze a rich spatial model that allows for spillovers, matching and income tax, in a setting with multiple work and residential locations and very general worker heterogeneity. The conventional consumer surplus captures part of the benefits and is calculated based on predictions of changes in travel demand and transport costs. The issue is to determine which so-called wider impacts to add to this. We find that adding the change in total output as a wider impact leads to double-counting of benefits. The output change due to spillovers should be added, while the output change due to matching is already partly included in the consumer surplus. These results are useful for applied cost-benefit analysis of transport policies.

We explore how transport improvements impact agglomeration defined as accessibility and thereby productivity in mid-Sweden including Stockholm 1995–2006. We apply an accessibility index derived from a multi-modal transport model. This is a more accurate measure of agglomeration than those previously used and also necessary for understanding how governments can impact agglomeration, and thereby productivity, by transport investments. We regress temporal changes in wages on temporal changes in agglomeration by applying a FE estimator. We deal with the potential endogeneity using a novel instrumental variable. Our best estimates of the agglomeration elasticity on productivity lie within the interval 0.028–0.035.

In this paper we study the effect of contract design on the performance of railway maintenance in Sweden, using a panel data set over the period 2003–2013. The effect of incentive intensity is estimated, showing that the power of incentive schemes improve performance as measured by the number of infrastructure failures. In addition, we show that the structure of the performance incentive schemes has resulted in a reallocation of effort from failures not causing train delays to failures causing train delays, with a substantial increase in the former type of failures. This signals a deteriorating asset condition, which highlights the need to consider the long-term effects of this incentive structure. Overall, this work shows that the design of the incentive structures has a large impact on the performance of maintenance, and that the estimated effects are important to consider when assessing contract designs within this field.